Where such milling cutters are used as roughing cutters, their peripheral cutting edge is frequently provided with an interrupted tooth profile, the so-called “cord”. In addition, a specially formed flute is frequently provided on the cutting surface which, however, is of only minor importance within the context of this invention.
The purpose of the cord is to influence the cutting edge length, the chip formation and the cutting force in such a way that they are advantageous for roughing by the chip receiving an optimum width, whereby it breaks quickly and can then be conveyed away without any problems despite the high chip removal rate. Very narrow chips, for example, break relatively poorly and tend to form long strands. Wide chips, such as they are produced by tools with a continuous cutting edge, also break poorly due to their high strength and require very high cutting forces. The fact that tools with divided cutting edges obtain poorer surface qualities is deliberately accepted so far.
Such roughing cutters with a cord are thus particularly suitable for use in so-called HPC (high performance cutting), in which particularly large chip removal rates are realized.
Roughing cutters with cords have been used for a long time and have so far shown very good suitability for everyday use, which did not give any particular cause for complaints.
If the chip removal rates are increased significantly by fully exploiting the capacity limit of the cutting tool, it is suddenly evident in the known roughing cutters with cords that the peripheral cutting edges may break out where they are provided with the tooth profile forming the cord. This shortens the life span of the tool. In particular, this problem arises in the case of solid-carbide tools, whose cutting edges reach such long life spans, even with the high stresses of high-performance chip removal, that failures of the tooth profile forming the cord due to break-outs occur to an, in part, significant extent even though the cutting edges as such would still be sufficiently sharp.
It is therefore the object of the invention to provide a milling cutter with a profile forming the cord that is more durable.